It is necessary that various medical wastes, human cadavers, test animals, discarded medical instruments and bandages, among other things, be properly processed so that they are reduced to inert, sterile material. Very often, these forms of biomass and other related volatile solids have infectious or even deadly bacteria or viruses in them, or may contain powerful and perhaps illicit drugs, all of which must be destroyed. These forms of biomass and medical instruments and the like typically contain extremely large percentages of hydrogen, carbon, and also a number of trace elements, such as nitrogen, sulphur, iron, chlorine, magnesium, manganese, sodium and potassium, among others. It is desirable to heat all of these materials so that they are converted to gasses, preferably harmless gasses, which gasses are either elemental hydrogen, oxygen, which oxidize to water vapour and to residual carbon dioxide and to residual compounds and elements. The residuals, which are typically solids at ambient room or environmental temperature, should end up as inert mineral materials.
In order to accomplish the reduction of such biomass waste and related volatile solids into relatively inert gasses and minerals salts, alloys, or other compounds, it is necessary to heat these materials sufficiently so as to break the chemical bonds between the molecular structures. Intense heating is required to break the various chemical bonds, such as hydrogen-carbon bonds. It is necessary that essentially all of the hydrogen-carbon bonds be broken, as the bonds are typically found in organic material, which organic material must be destroyed. Such extreme heating of such materials in this manner is known as pyrolysis, which is defined as chemical decomposition by action of heat. Typically, such pyrolysis is carried out at temperatures in the order of 1,000.degree. C. for periods of about 6 to 8 hours. The ash material that is ideally produced, which ash material is composed mostly of mineral salts, will glow an orangey-red colour when it is at 1,000.degree. C. and will ultimately be a white ash when it has cooled. The main constituents of the organic materials, namely hydrogen and carbon, are gasified, to form mainly carbon dioxide and water.
What is not desirable as an end product, and is even unacceptable, is black colored ash. Such black colored ash indicates that the ash is not completely reduced and there is still carbon and hydro-carbon material, among other materials, in the ash. The ash, therefore, might contain organic material therein, which organic material might even be in the form of bacteria or viruses, or might be chemical compounds, including toxic materials, such as dioxins, furans and other organo-chlorides.
Basically, the heat causes the waste material to process itself, which processing mostly includes the pyrolytic breaking of the various chemical bonds, such as hydrogen-carbon bonds so as to permit gasification of all the materials possible.